Introduction To Pharmacology Flashcards

Question

What do carriers do?

Answer 1

Never has a continuous path. Driving force = electrochemical gradient Slow Can become saturated e.g. GLUT

Answer 2

1) The carrier is open to the outside 2) X enters and binds to binding site 3) Outer gate closes - X still bound 4) Inner gate opens 5) X enters cell

Answer 3

Flux limited by # of carriers and speed of carrier cycle. Jmax = conc high enough to occupy all carriers.

Answer 4

Pumps Cotransporters Exchangers

Answer 5

- Requires a solute whose electrochemical gradient provides the energy. - Move both in (symporters e.g. Na/glucose) - Can become saturated.

Answer 6

Total conc of all particles free in a solution. mOsm = milliosmoles per kg of water

Answer 7

Gated ion channels e.g. potassium channel. Driving force = electrochemical gradient

Answer 8

Solutes move in opposite directions (antiporters e.g. Na/Ca).

Answer 9

He won a Nobel prize for studying acetylcholine as an agent in the chemical transmission of nerve impulses.

Answer 10

A chemical, peptide or protein which communicates between cells.

Answer 11

- released in sufficient amounts to produce a biological action on a specific cell in a time frame. - applying a sample will have the same biological effect - interference on synthesis, release or action will stop/control response.

Answer 12

They are extracellular signal molecules --> bind to receptors on target cells --> initiates intracellular signals which alter cell behaviour through effector proteins (cell signalling)

Answer 13

Converting extracellular signals to intracellular.

Answer 14

- contact-dependant - autocrine - synaptic - paracrine - endocrine

Answer 15

Shortest type of signalling. e.g. immune responses and development (delta-notch signalling)

Answer 16

Extracellular mediators act locally - stored in vesicles or synthesised on demand. e.g. histamine, nitric oxide (vessel diameter), prostaglandins.

Answer 17

Similar to paracrine but activates itself.

Answer 18

Uses synapses - fast - to specific cells. Mediators - neurotransmitters e.g. ACh (neuromuscular junction &heart), Noradrenaline (on heart)

Answer 19

Long distance - uses hormones through the blood. Slow and non-specific. Hormones can be protein (insulin), aa derives (adrenaline) or steroid (estradiol).

Answer 20

1) small molecular - regulated by specific enzymes. 2) peptides - regulated by transcription - depends what genes are active and cells can produce multiple types of mediator. Vesicles can store more than one.

Answer 21

- preformed and stored in vesicles until released by exocytosis - rapid - includes noradrenaline and insulin --> conc usually mM which is good so we can have high conc for response. - on demand synthesised and released by diffusion or constitutive secretion - slower to act - e.g. nitric oxide and prostaglandins.

Answer 22

Studies showed quantal nature which suggested packages.

Answer 23

Enzymes can stop it e.g. acetylcholinesterase. The NT can also be taken back into the neuron or supporting cells e.g. glia - this is due to specific transporters in membrane

Answer 24

Otto Loewi

Answer 25

From tyrosine --> dopamine --> noradrenaline ---> adrenaline Enzymes required for each step.

Answer 26

Any molecule which binds to a receptor - can be antagonist or agonist Hydrophilic or hydrophobic

Answer 27

Mediator in the body which binds to a receptor - produces a response e.g. ACh, noradrenaline, insulin

Answer 28

All cells have multiple types of receptors - can integrate information Receptors can use similar transduction mechanisms = amplify signal

Answer 29

Molecules can act on more than one type of cell type. Allows coordinated responses.

Answer 30

Proteins - recognition sites which can bind to a molecule and modulate activity of the cell

Answer 31

- each has transmembrane spanning segments - each has a ligand binding domain - ligands here are hydrophilic

Answer 32

1) Ligand-gated ion channels (ionotrophic) - could cause electrical signals - takes milliseconds 2) G protein-coupled receptors (metabotropic) - could contact muscles - takes seconds 3) Kinase-linked receptors - can change enzyme activity - takes hours e.g. insulin receptor 4) Nuclear (intracellular) - more channels in cell membrane - takes hours

Answer 33

Polypeptides with multiple domains Ligands here are hydrophobic Act as a transcription factor - binds to DNA and regulated gene expression e.g. oestrogen receptors

Answer 34

Most small mediators = ligand or g protein-coupled Peptide hormones = g protein-coupled or kinase-linked Steroid = nuclear

Answer 35

- Ion channels - involved in fast synaptic transmission - agonists = neurotransmitters - made of 3-5 subunits - had central aqueous pore - channel closes when agonist removed e.g. NAChR

Answer 36

Nicotinic Acetylcholine Receptor - excitatory ligand gated ion channel - on every skeletal muscle - in NMJ and autonomic NS - has 5 subunits - agonist = ACh or nicotine - when bind cause depolarisation as ions flow through

Answer 37

Bind to ligand gated ion channels (GABAa receptors) - causes inhibition as cause hyperpolarisation

Answer 38

- Single transmembrane protein which spans membrane 7 times (7TM) - >800 genes code for these - Interacts with an intracellular G protein (heterotrimeric GTP-binding protein) - has 1 alpha, 1 beta, 1 gamma subunit e,g, MAChR

Answer 39

1) beta and alpha units are bound to the receptor 2) when ligand binds - g protein changes and causes GTP to bind to alpha instead of GDP 3) G protein leaves receptor 4) a-GTP and beta-gamma dissociate 5) they can bind with their effectors 6) when GTP --> GDP again - trimer reassembles

Answer 40

- ion channels - enzymes: adenylyl cyclase, phospholipase C

Answer 41

Small diffusible molecules that spread a signal Amplify a signal

Answer 42

GAs - stimulates - more adenylyl cyclase, more cAMP and more protein kinase A GAi - inhibits - less adenylyl cyclase, less cAMP, less protein kinase A cAMP - secondary messenger

Answer 43

Gaq (alpha subunit) activates phospholipase C which breaks down PIP2 into IP3 & DAG. IP3 triggers release of calcium from the ER.

Answer 44

Gs - activates adenylyl cyclase - e.g. adrenergic B1/2 Gi - (a) inhibits adenylyl cyclase or (By) activates potassium channels - e.g. adrenergic a2/muscarinic M2 Gq - activates phospholipase C - increases calcium e.g. adrenergic a1/muscarinic M1/M3

Answer 45

A known chemical substance which, when administered, causes a biological response. Can interfere with synthesis, storage, release, degradation or receptor-dependent response produced by a mediator.

Answer 46

Lab test where we investigate the function of mediators, measure toxicity and test phamacological activity.

Answer 47

- drug action must be explicable - drug molecules must be bound to cells/tissues to produce an effect - drug molecules must exert a chemical influence on 1 or more parts of a cell to produce a pharmacological response

Answer 48

- enzymes - transporters - ion channels - receptors

Answer 49

Drug which inhibits the response of an agonist - competes with agonist and binds instead DO NOT MAKE A RESPONSE

Answer 50

When drugs lack specificity - drugs will bind to its specific receptor anywhere.

Answer 51

e.g. CAR T immunotherapy uses this signalling to kill cancer cells - engineered by altering genome of T cells

Answer 52

e.g. mast cells secrete histamine - antihistamines will block histamine receptors e.g. prostaglandins (a type of eicosanoid) are formed from different enzymes - paracetamol can target these enzymes e.g. nitric acid relaxes blood vessels - viagra inhibits an enzyme - prolongs NO action

Answer 53

e.g. can block voltage gated sodium channels - prevent action potential - used as local anaesthetic - lidocaine e.g. Botulinum toxin - from bacteria - cleaves proteins needed for synapses e.g. amphetamines increase noradrenaline by displacing it from vesicles e.g. fluoxetine blocks 5HT reuptake - antidepressant

Answer 54

Hormones are secreted from here into blood. Have close proximity to capillary beds. Found in endocrine tissues or glands (NO DUCTS)

Answer 55

Enables signalling along long distances Slow Specific to receptors - not specific organs or tissues

Answer 56

Protein e.g. Insulin Amino acid e.g. adrenaline Steroid e.g. estradiol

Answer 57

- from amino acids - released by exocytosis by secretory granules - receptors = cell membrane surface - response - s to min

Answer 58

- derived from tyrosine (requires specific enzymes) - released from vesicles via exocytosis (except thyroid hormone) - receptors = cell membrane surface (except thyroid hormone) - response = s to min (except thyroid)

Answer 59

- metabolite of cholesterol (needs enzymes) - lipid soluble = diffuses out - diffuses into cells and binds to nuclear receptors - response = hours to days

Answer 60

- Pituitary - Thyroid - Parathyroid - Adrenals - Ovaries - Testes - Pancreas

Answer 61

- hypothalamus - kidneys - GI tract - heart - liver - adipose tissue

Answer 62

Adenohypophysis - developed from upward projection of pharynx - troph cells are stimulated by hormones from hypophyseal portal system from hypothalamic neurons

Answer 63

Neurohypophysis - developed from downward projection of brain - releases hormones from large diameter neurones into bloodstream

Answer 64

Tropic hormones - stimulate effects from other hormones - GH, ACTH, TSH, FSH, LH, Prolactin Posterior - ADH & Oxytocin

Answer 65

Secretes T3 & T4 (amino acid derived) - these depend on hypothalamic-pituitary hormones and iodine These transport across cell membranes by facilitated diffusion and bind to nuclear receptors. This regulated metabolism, development and growth

Answer 66

Parathyroid hormone (peptide) regulates plasma calcium and phosphate and targets bone, intestine and kidneys.

Answer 67

High plasma calcium is sensed by chief cells - lower PTH, lower kidney reabsorption, less bone resorption and low intestinal absorption.

Answer 68

Releases steroid hormones: glucocorticoid (cortisol), mineralcorticoid (aldosterone) Zona glomerulosa - mineral Zona fasciculata - gluco

Answer 69

Chromaffin cells release adrenaline Noradrenaline is also released

Answer 70

Hypothalamus releases CRH - this causes the anterior pituitary to release ACTH - causing adrenal cortex to release cortisol. Cortisol inhibits CRH and ACTH release

Answer 71

Steroid hormones: oestrogen and progesterone This gland can switch from negative to positive feedback

Answer 72

Leydig cells secrete steroid hormone - testosterone

Answer 73

Somatic NS Afferent to CNS (brain and spinal cord) Efferent to somatic NS (voluntary) Skeletal muscles

Answer 74

Visceral nerves (sensory part of peripheral NS) Afferent to CNS Efferent to autonomic NS (involuntray - motor part of peripheral NS) Smooth muscle, cardiac, glands ect.

Answer 75

(part of peripheral) Sympathetic - fight or flight - coordinated full body or organ specific Parasympathetic - rest and digest - organ specific

Answer 76

- eye - dilation - heart - increase heart rate - blood vessels - constricting - lungs - bronchiole dilatione - liver - reproductive systems

Answer 77

- heart - decrease heart rate - eyes - GI tract - bladder - reproductive organs

Answer 78

Innervate the same tissues but have opposite effects - work synergistically. Except for sweat glands, hair, blood vessel sm and adrenal medulla which are mainly sympathetic

Answer 79

Preganglionic neuron in CNS Postganglionic neuron in peripheral ganglion both symp and parasymp have this organisation

Answer 80

Always cholinergic - release ACh ACh activated nicotinic ACh receptors on postsynaptic cell

Answer 81

Short cholinergic from thoracic and lumbar spinal cord - long adrenergic postganglionic Target tissue express alpha and beta adrenergic receptors

Answer 82

Adrenal medulla - chromaffin cells are similar to postganglionic neurones but release adrenaline - target is a and b adrenergic receptors

Answer 83

Long cholinergic neurons from brainstem and sacral spinal cord Short cholinergic postganglionic neurones Target tissues express muscarinic ACh receptors

Answer 84

Cranial nerve 10 Carries 80% of parasympathetic outflow Also carries visceral afferents

Answer 85

The spinal cord - also receives sensory afferent and brainstem input Brainstem nuclei - mediate autonomic reflexes Forebrain - cortical control could cause autonomic output e.g. anxiety Visceral afferents - sensory from organs takes priority over cortical e.g. needing the toilet badly

Answer 86

Feeding Thermoregulation Circadian rhythms Water balance Sex drive Reproduction

Answer 87

Acetylcholine and NA They act on nAChRs, mAChRs, alpha and beta adrenoceptors

Answer 88

Gas - stimulates 1) stims adenylyl cyclase 2) This increases cAMP 3) This increases PKA Gai - inhibits 1) inhibits adenylyl cyclase 2) lower cAMP 3) lower PKA

Answer 89

Part of g protein It increases phospholipase C - increases IP3 + DAG - this increases calcium levels

Answer 90

Gs, Gi, Gq They are g proteins Gs - alpha - activated adenylyl cyclase Gi - alpha - inhibits adenylyl cyclase - betadelta - activates k+ Gq - activates PLC - increase calcium

Answer 91

- Nicotinic - agonists = nicotine, antagonist = curare - Muscarinic - agonists = muscarine, antagonist = atropine Both have ACh as agonist

Answer 92

M1, M3, M5 - These have Gq -> increased PLC - Increased calcium M2, M4 - These have Gi - inhibits adenylyl cyclase

Answer 93

M1 = autonomic ganglia, glands, cerebral cortex - allows for gastric secretion and CNS excitation M2 = atria, CNS - cardiac and neural inhibition M3 = exocrine glands, smooth muscle, blood vessels - gastric and salivary secretion, GI SM contraction, vasodilation, eye accomodation M4 = CNS - enhanced locomotion M5 = substantia nigra, salivary glands - not known

Answer 94

Parasympathetic stimulation activated M2 receptors in atria - betadelta subunit will open k+ channels - moves out - more negative - decreases HR - slow AV conduction - decrease atria force

Answer 95

Gq coupled - contract smooth muscle (bronchoconstriction, GI motility, bladder voiding) Stimulate secretion from glands (mucus, lacrimal glands, salivary, sweat)

Answer 96

low BP, high saliva, high tear flow, high sweat, nausea overdose: death from cardiac and resp failure

Answer 97

Inhibit secretion of saliva, tears, sweat ect. Relax smooth muscle Dilate pupils Increase heart rate

Answer 98

Cholinomimetic Inhibit acetylcholinesterase Anticholinesterase drugs: 1) long acting (irreversible) 2) nerve gas (organophosphates, pesticide)

Answer 99

On tissues responding to postganglionic sympathetic neurons Beta - All Gas - all increase cAMP

Answer 100

NA (sympathetic neurones), A (chromaffin cells) bind to B1 receptors on ventricles and nodes 1) binds 2) stims adenylyl cyclase - more cAMP and PKA 3) This phophorylates calcium channels 4) calcium enter - contraction

Answer 101

B2 activation - Gas activation - stims adenylyl cyclase - more cAMP, more PKA - phosphorylates SM

Answer 102

Adrenaline - cardiac arrest & anaphylaxis B2 selective - bronchodilator (salbutamol)

Answer 103

Can treat hypertension, heart failure, anxiety But can cause bronchocontriction and cardiac depression

Answer 104

Endoderm (GI lining) Mesoderm (CV lining) Ectoderm (Epidermis) - in every organ

Answer 105

- protection - skin - absorption - SI - barrier - BBB - diffusion - lung - secretion - gland

Answer 106

- can import or expel substances - have tight junctions - have apical (faces external environment) and basolateral domains with differing membrane properties (polarised)

Answer 107

Entirely! - avascular (no blood vessels) - lack extracellular fibres - little extracellular space

Answer 108

Yes! There are differences between the apical and basal membranes (both specialised in different ways)

Answer 109

Separates cells from underlying connective tissue (collagen IV). ECM proteins secreted by epithelial cells: collagens, laminins, proteoglycans Structural support - basal lamina, reticular lamina (anchors BM to connective tissue below)

Answer 110

Impede paracellular (between cells) movement Protein strands (claudins) determine tightness - 24 claudin genes Have high barrier function e.g. renal thick ascending limb Are leaky e.g. proximal tubule Variation in the permeability

Answer 111

Form belt around cell - under tight junctions - linked actin and cadherins Disruption can cause spread of cancer (metastasis)

Answer 112

- underlying mesenchymal cells form epithelium as cadherins change expression - this is epithelial-mesenchymal transition (EMT) - used for embryonic development and cancer metastasis

Answer 113

Lateral communication between cells - allows small molecule diffusion between cytoplasms - cells electrically coupled

Answer 114

- Tight junctions - Adhering junctions - Gap junctions - Desmosomes

Answer 115

Strong adhesion - has extracellular domains (cadherin). Anchor proteins (plaques) link cadherin domains to intermediate filaments There are some myosin filament interactions - contract

Answer 116

Actin-linked cell matrix junction Hemidesmosome

Answer 117

From stem cells - tissue homeostasis Intestines - 5 days Lungs - 6 months

Answer 118

Simple - single layer Stratified - many layers (skin) Pseudostratified - upper resp Transitional - urothelium

Answer 119

Simple squamous - thin, allow rapid passage Simple cuboidal - secretion/absorption of molecules by active transport - some have cilium

Answer 120

Simple columnar: may have cilia/microvilli, majority of GI tract, in fallopian tubes, in some respiratory Pseudostratified: single layer but looks like more, can be ciliated - these have goblet cells

Answer 121

Stratified squamous: most common stratified, in areas of abrasion Stratified cuboidal: less common, glands

Answer 122

Stratified columnar: rare - in pharynx, anus, male urethra, embryo Transitional: round cells when relaxed

Answer 123

Mucus: mucus glands Protein: serous glands e.g. salivary Sebum: sebaceous glands e.g. oils on face

Answer 124

- voluntary movement of bones - control of inspiration by diaphragm - skeletal-muscle-pump - returns venous blood

Answer 125

Striated Myofilaments - myofibril - muscle fibre - fascicle T tubules and sarcoplasmic reticulum form triad H and I change shape A doesn't

Answer 126

ACh at neuromuscular junction - action potential in membrane of muscle Wave of depolarisation through t-tubule to interior of cell - runs near 2 areas of SR - triad Reaches sarcoplasmic reticulum Increase of intracellular calcium

Answer 127

1) ATP binds to myosin head - dissociation of actin-myosin complex 2) ATP is hydrolysed - returns to resting state 3) crossbridge forms - myosin head binds to actin 4) Pi released 5) change in myosin - power stroke - filaments slide 6) ADP released 5 times a second

Answer 128

~ 300 heads each head cycles 5x a second

Answer 129

Type 1 (slow oxidative) - non fatigue, red, low glycogen, high mitochondria e.g. soleus Type IIa (fast oxidative) - non fatigue, red, some glycogen, higher mitochondria e.g. gastrocnemius Type IIb (fast glycolytic) - fatigable, white, high glycogen, anaerobic, few mitochondria e.g. biceps

Answer 130

Slow - half the diameter and take longer to contract Fast - take 10 msec or less

Answer 131

Involuntary contraction - in three phases: latent - contraction - relaxation

Answer 132

Isometric - muscle at fixed length - tension generated e.g. plank Isotonic - muscle stimulation causes a change in length e.g. bicep curl

Answer 133

Linked to food poisoning - muscle weakness, paralysis - endoproteinase which cleaves exocytosis of ACh can be used for cross-eyedness (strabismum), uncontrolled eye movements (blepharospasm), and botox ADD TOXINS FOR ALL CHANNELS

Answer 134

- skin - largest organ - 12-15% of body weight - layers by 4 months in utero, 3rd trimester skin hardens (pigment absorbs light, blood and fat scatters light)

Answer 135

Epidermis (epithelia) Dermis Hypodermis (adipose tissue)

Answer 136

2mm in soles/ 0.2 mm in eyelid Fibroblasts produce ECM proteins: collagen, laminin/fibronectin 2 zones: - papillary - thin loose connective tissue, motibility of leukocytes, mast cells and macrophages - reticular - thick dense irregular - adipocyte clusters Has all accessory organs: hair, nail, sweat glands Rich layer of blood, nerve endings and lymphatic vessels

Answer 137

Wavy boundary - dermal papillae (raised areas e.g. fingerprint), epidermal ridges The papillae facilitate nerve fibres reaching close to the surface

Answer 138

keratinised stratified squamous epithelium

Answer 139

Stratum corneum lucidum - stress protect granulosum spinosum basale Thin doesn't have lucidum - thick does No blood vessels Self-regeneration

Answer 140

Has keratinocytes - in touch with basement membrane (stem cells) Melanocytes give skin colour Merkel/tactile cells connected to sensory nerves

Answer 141

Release melanin - UV absorb, antioxidant pheomelanin - red/yellow eumelanin - brown/black Pigment of skin = melanin + carotine (in fat + corneum) + blood Form melanosomes which are phagocytosed by keratinocytes

Answer 142

Several keratinocyte layers - usually thickest (unless thick skin - corneum) Produce keratin filaments - keratinocytes are linked by desmosomes so water retention Dendritic cells present

Answer 143

3-5 layers of flat keratinocytes Have dark staining granules Cells undergo apoptosis Produce glycolipid-filled vesicles which produce barrier between stratum spinosum

Answer 144

Most superficial 15-30 layers of flattened corneocytes (dead keratinocytes) - stratum disjunctum: have corneodesmosomes which regulate desquamation - stratum compactum have a cornified envelope full of keratins - enclosed within proteins and surrounded by lipid envelope

Answer 145

Derivative of stratum corneum Packed with keratin New cells added in nail matrix Iron deficiency = fat/concave Hypoxemia = clubbed

Answer 146

Filament of keratinised cells from follicle. Hair bulb - in dermal papilla - hair matrix above Lanugo (soft hair) - vellus - terminal medulla - loose cells cortex - keratinised cuboidal cells cuticle - surface scaly cells

Answer 147

Eccrine/merocrine sweat glands - watery perspiration, controlled by SNS, temp regulation Apocrine sweat glands - cells pinch off and released into scent follicles - respond to stress and sex - armpits and gentials Holocrine sebaceous glands - cell disintegrates - oily skin and hair Ceruminous glands - e.g. earwax Mammary glands

Answer 148

Physical - keratin scaffold Biochemical - mild acidic, sebaceous glands (FAs inhibit bacteria, C6H) Immunological - dermal and epidermal langerhans cells

Answer 149

Immunological barrier - process antigens

Answer 150

Fat soluble - increases intestine absorption of Calcium Previtamin D3 in the keratinocytes is photolysed by UV acts via a nuclear receptor prohormone - first step Photochemical reaction

Answer 151

Anterior hypothalamus senses body temp Receptors Insulation Sweating Vasodilation/constriction There are arteriovenous anastomoses - have sympathetic innervation - low temp - increase innervation ect.

Answer 152

Striated - branched with intercalated disks There are electrical coupling between myocytes by gap junctions

Answer 153

Involved in mechanical control of organ systems Non-striated - multiple actin fibres join at dense bodies Can be multiunit or unitary

Answer 154

Depolarisation activates L-type calcium channels in T-tubule membrane - influx of calcium There's a mechanical tethering between the L-type channels in t-tubules and Ca channels (Ryanodine receptors) in sarcoplasmic reticulum - they open

Answer 155

Yes! but only one branch of t-tubule is near SR (no triad)- dyad at the Z line No mechanical interaction between t-tubule receptors and ryanodine receptors The calcium instead triggers the receptors on the SR Calcium induced calcium release

Answer 156

1) across the membrane by plasma membrane calcium ATPase (PMCA) or Na/Ca exchanger 2) back into SR via calcium ATPase

Answer 157

No t-tubules, no triads or dyad - instead have shallow invaginations - caveolae Have two parts of SR - peripheral (next to caveolae) and central L-type ca channels still activate from action potential Activation of ryanodine receptors - calcium induced calcium Activation of Gq-coupled - IP3 production - IP3 receptors in SR (calcium channels)

Answer 158

Calcium binds to TnC - causes TnT to pull tropomysosin and TnI out of the way Myosin can now bind When calcium dissociates - everything goes back to normal

Answer 159

No troponin!! There's calponin and caldesmon instead. Calmodulin is stimulated by calcium Myosin light chain is phosphorylated by myosin light chain kinase - allows formation of crossbridge To stop - de-phosphorylate with MLCP

Answer 160

Motor neuron and muscle fibres

Answer 161

Primary - distribute gases Secondary: - fast chemical signalling - dissipation of heat - mediated inflammatory and host defences

Answer 162

Left - systemic - Parallel pathway from left to right - Usually through single capillary bed - two in kidney ect. Right - pulmonary - single pathway from right to left

Answer 163

Radius decreases with branching Combined cross-sectional area in daughter cells>parent cells CSA increase highest in capillaries

Answer 164

Endothelial cells -> elastic fibres -> collagen fibres -> smooth muscle cells Adventitia (outside) -> Media -> intima

Answer 165

Large arteries - high compliance and can cope with high pressures

Answer 166

Medium sized - there are smooth muscle cells arranged circumferentially - can vasoconstrict and dilate

Answer 167

Connect to capillaries - have precapillary sphincters which monitor blood flow also have terminal regions - metarterioles smooth muscle regulated flow - regulated microcirculation

Answer 168

Are porous - exchange nutrients and waste - excellent reservoirs - have thin smooth muscle

Answer 169

Only endothelial and basement membrane - exchange gases, water, nutrients and waste Three groups: - fenestrated - continuous - sinusoidal (discontinuous)

Answer 170

Fluid transfer in capillaries Jv = Kf [(Pc-Pi) - (Pi c - Pi i) + = filtration, - = absorption Jv = fluid movement Kf = hydraulic conductance Pc/i = Capillary/intestinal hydrostatic Pi = oncotic Pc declines down the capillary

Answer 171

Drains excess interstitial fluid Maintains blood volume Transports dietary lipids Immunology

Answer 172

AV (mitral + tricuspid) connected by chordae tendinae and papillary muscles

Answer 173

Epicardium, myocardium (have cells connected by intercalated disks) and endocardium - all electrically active - have conducting (spread AP) and contractile (contract due to AP) cells

Answer 174

Has gap junctions - allows current to flow Desmosomes anchor fibres together Undergoes excitation-contraction coupling

Answer 175

Depolarisation starts at SAN - spreads to AVN by gap junctions or conducting pathways. There's an AV ring - prevents spread to ventricle then carried to ventricle muscle

Answer 176

1) Atrial systole - atrial depolarisation (contracts) - v fill 2) Isovolumetric ventricular contraction (mitral & tricuspid close) 3) Rapid ventricular ejection - semi lunar valves open 4) Reduced ventricular ejection - ventricle repolarisation 5) Isovolumetric ventricular relaxation - SLV close 6) Ventricular filling LOOK AT GRAPH

Answer 177

Na+ = depolarise Ca+ = contracts myocytes K+ = repolarises Pacemaker current

Answer 178

Electrodes detect currents from different angles of the heart

Answer 179

P wave = atria depolarisation QRS = ventricular depolarisation T wave = ventricular repolarisation

Answer 180

Arteries - high pressure, have low compliance, volume = stressed volume

Answer 181

Has tonically active smooth muscle Have highest resistance to blood which is effected by: - sympathetic nerves (increases resistance) - alpha receptors = contract skin ect., beta = relax skeletal muscle and heart arterioles - need a balance - catecholamines e.g. adrenaline - vasoactive substances e.g. NO

Answer 182

Low pressure - controlled by diameter of arterioles

Answer 183

Low pressure Has less elastic than arteries Has largest percentage of blood in CV - unstressed volume Large capacitance Has symp nerve fibres in smooth muscle + alpha adrenergic receptors - reduced capacitance - decreased unstressed volume

Answer 184

V = Q/A Q - flow (mL/s) A - cross sectional area (cm) Small vessels have higher velocity

Answer 185

Q (mL/s) = pressure difference (mmHg)/resistance

Answer 186

R = 8nl/pi x r^4 n = viscocity l = length of blood vessel Directly proportional to length and viscosity Inversely proportional to fourth power of radius Series resistance = within an organ: artery-arteriole-capillary ect. Arterioles have largest decrease Parallel resistance - branches - no loss of pressure

Answer 187

Arterial (Pa) - oscillations reflect diastolic and systolic pressure Venous (Pv) - by veins and venules (less than 10mmHg) Pulmonary circulation has lower pressure Greatest pressure drop in arterioles

Answer 188

PP = systolic - diastolic pressure MAP = diastolic + 1/3 pp

Answer 189

Baroreceptors - in carotid and aortic sinuses Solitary sinus receives signal and directs SNS and PNS changes via medullar CV centres PNS --> vagus nerve --> SAN SNS --> SAN --> arteriole vasoconstrict --> vein vasoconstrict --> cardiac muscle contracts more There's also chemoreceptors - increase BP if low O2 (low pH)

Answer 190

RAAS: low perfusion in kidney - renin released - converts angiotensinogen to angiotensin I to II. Angiotensin II increases aldosterone - increases Na and releases ADH - more water - also vasoconstricts arterioles

Answer 191

Desensitise baroreceptors - reduces stretch sensitivity - reduced sympathetic inhibition - hypertention not corrected people here don't usually experience a dip in BP at night - higher risk of heart attack ect. Can be treated by lifestyle changes, ACE inhibitors, Ca channel blockers, diuretics, beta blockers

Answer 192

Cellular components in plasma - erythrocytes - leukocytes - platelets

Answer 193

Albumin Fibrinogen - precursor of fibrin Immunoglobulins Proteins in coagulation cascade

Answer 194

Most abundant non-nucleated biconcave disks 3 main functions: co2/o2 carriage, buffering

Answer 195

Granulocytes: neutrophils (phagocyte) eosinophils (combat viruses and parasites) basophils (release histamines ect.) Non-granular: lymphocytes (mature into B and T) monocytes (macrophages and dendritic)

Answer 196

Bud off megakaryocytes in bone marrow - thrombopoesis in response to thrombopoetin and IL-3 1) Platelets bind to TPO 2) megakaryocytes not generated 3) If no platelets bind to TPO (as little platelets) - TPO stimulates megakaryocytes and platelets 150000 - 450000 in blood

Answer 197

Prevention of a haemorrhage 1) vasoconstriction (serotonin, thrombin ect.) 2) Increased tissue pressure 3) platelet plug (primary haemostasis) 4) clot formation (secondary haemostasis)

Answer 198

No nucleus - have mitochondria, lysosomes, peroxisomes, alpha granules (VWF, fibrinogen, clotting factor, platelet derived growth factor), dense factors (ATP, Ca) Have lots of receptors Tubulin helps maintain shape Cytoskeleton has actin and myosin

Answer 199

1) platelet adhesion 2) platelet activation 3) platelet aggregation

Answer 200

Exposed endothelium exposes collagen - VWF binds to collagen and platelet receptors Endothelial cells also release VWF Binding cause IC cascade - activate

Answer 201

Cascade causes: - secretion/exocytosis of dense and alpha granules (VWF and ADP - both activate it further) PDGF - wound healing Thromboxane - vasoconstrict and inflammation Cytoskeleton changes Expression of fibrinogen receptors

Answer 202

Fibrinogen binds to platelet receptors - forms bridges between platelets - this plugs the break in endothelium Eventually actin and myosin contract - stronger plug

Answer 203

More permanent fibrin mesh Mass of erythrocytes, leukocytes, serum and the mesh already there Thrombus = intravascular clot

Answer 204

Intrinsic (slow) - factors in blood contact with negatively charged membrane of platelet - causes cascade of protease reactions - ends in factor Xa Extrinsic - endothelium injury causes tissue factor (receptor) to become activated when in contact with factor VII - results in factor Xa xa from both enter common pathway - generates thrombin - produces fibrin

Answer 205

Normal endothelial cells - through paracrine and anticoagulant factors Paracrine factors - e.g. prostacyclin promotes vasodilation - inhibits platelet steps Many anticoagulant factors - some stop thrombin Promotion of pro-thrombotic state via vascular damage and hypoxia Turbulent flow causes endothelial injury - caused by stenosis, large radius and high velocity

Answer 206

Thrombosis: Abnormal blood flow Endothelial injury Hypercoagulability

Answer 207

water - 1.5L per day in urine (1.1 by respiration, stools and sweat) Na+ - 140 mmoles per day in urine (10mmoles in stool and sweat)

Answer 208

from T12 to L3 - around 10cm long and 5.5cm wide Capsule Cortex Medullary ray Pelvis Ureter

Answer 209

Superficial nephron (85%) in the cortex Juxtamedullary nephron - 15%

Answer 210

Ectopic kidney Horseshoe kidney - fused Renal agenesis - lack/failure to develop

Answer 211

Fall in GFR (usually 125ml/minute) - increase in serum urea and creatinine Can be: - acute (reversible) - chronic (irreversible)

Answer 212

Chronic has longer history Haemoglobin level lower in chronic Renal size lower in chronic Chronic has peripheral neuropathy

Answer 213

Thickening glomerular membrane --> damaged glomeuli --> scarring --> reduced renal size

Answer 214

Describes the symptoms of renal failure - hypertension - nausea - anaemia - bone diseases - neuropathy ect.

Answer 215

As the stages progress - GFR decreases Uraemic syndrome becomes more severe Serum biochemistry gets severe Begins with anaemia and bone disease -- dialysis

Answer 216

30% - glomerulonephritus 25% - diabetes 10% - hypertension

Answer 217

Drain excess interstitial fluid and return to blood via subclavian vein to maintain blood volume

Answer 218

Gap junctions Intercalated disks Sarcolemma T tubules Desmosomes

Answer 219

Glomerulus (200 micrometers) - ultrafiltration - 180 litres daily GFR = 125 ml/min Filtration - allows H2O and other molecules Ultrafiltrate - protein free plasma

Answer 220

Filtrate modification There is reabsorption in PCT and secretion from the blood in the tubules

Answer 221

Transcellular reabsorption Transcellular secretion Paracellular secretion and reabsorption

Answer 222

Produce transport proteins

Answer 223

Bulk reabsorption (70%) - 70% water and sodium - 100% glucose and amino acids 90% bicarb Sodium pumped out basally by Na/K pump - Na and glucose/phosphate(NaPiIIa)/aa then cotransport into the cell apically - water then diffuses paracellularly

Answer 224

- caused less Pi reabsorption - more lost in urine - issues in renal mineralisation - more stones - increased calcification

Answer 225

Bicarb reabsorption - NHE3 removes H+ (which reacts with bicarb apically - makes h2O and CO2 which can move in an dissociates back to bicarb and H+) and allows Na to move in - Na then leaves and takes bicarb into blood Knockout mice: - lower pH as bicarb falls - inhibits H+ secretion, Na/HCO3- transport

Answer 226

Foreign compounds e.g. penicillin Removal of plasma proteins bound substances

Answer 227

Concentration of urine Reabsorption of Na, Cl and water Reabsorption of Ca and Mg Site of action of loop diuretics

Answer 228

Thin descending - H2O moves out Thick/thin ascending - Na/Cl moves out

Answer 229

NKCC2 moves sodium, 2 chlorine and a potassium into the cell Sodium potassium pump - pumps sodium out CLCK - move Cl out basolaterally ROMK - move k+ out apically Calcium and magnesium move paracellularly

Answer 230

Recessive - 1 in 1 million Causes mutations in NKCC2, CLCK and ROMK - loop of henle - Cl accumulates, type 1 = NKCC2 mutations Causes hypotension Salt wasting Hypokalaemia Alkalosis Hypercalciuria - high calcium in urine Polyuria

Answer 231

Furosemide Bumetanide Effects NKCC2 - treats high blood pressure - has bartter's like symptoms

Answer 232

Early distal tubule - reabsorption of Na and Cl - reabsorption of Mg - sensitive to thiazide diuretics

Answer 233

NCC - cotransports Na/Cl into cell Na/K pump - pumps sodium out basolaterally CLCK - pumps calcium out basolaterally Mg and Ca enter through channels Thiazide stops NCC - treats high BP - has Gitelman's symptoms

Answer 234

Recessive - 1 in 40,000 - 1 in 1000 in Asian populations, 1% of Caucasian are carriers Affects NCC in distal tubule - salt wasting - hypotension - hypokalaemia - metabolic alkalosis - hypocalciuria - low calcium in urine

Answer 235

Xenopus oocyte expression studies - inject RNA - protein made - evaluate if the channel is made

Answer 236

Protection from hypertension

Answer 237

- K+ - dendrotoxin - ACh release - botulinum toxin, tetanus toxin - Ca2+ - w-conotoxin - Neuronal Na+ - tetrodotoxin, saxitoxin - Acetylcholinesterase - physostigmine, DFP - Muscle Na+ - tetrodotoxin, saxitoxin - AChR channel - a-bungarotoxin, d-tubocurarine

Answer 238

Concentration of urine Reabsorb Na and H2O Secrete K and H

Answer 239

Principal: reabsorb Na and H2O secrete K and H+ Intercalated: - alpha - H+ secretion, bicarb reabsorption - beta - H+ and Cl- reabsorption, bicarb secretion

Answer 240

ENAC - allows Na to enter cell apically ROMK - allows K+ to leave apically Aquaporin 2 - allows water in apically Sodium/potassium channel - allows sodium to leave basolaterally Kir2.3 - allows K+ to leave basolaterally Aquaporin3/4 - allow water to leave basolaterally

Answer 241

Stops ENaC in a principal cell - no Na+ can be reabsorbed Used for Liddle's syndrome - reduces blood pressure

Answer 242

Autosomal dominant - ENaC isn't removed - more Na Na+ retention - fluid retention Hypertension Hypokalaemia Metabolic alkalosis Low renin and aldosterone

Answer 243

COOH tail in beta or gamma subunit is mutated Proline is deleted - there is a reduced removal of ENaC Therefore more ENaC - more Na leaves - more water reabsorbed - causes hypertension (MAP = CO x HR) Also means more K+ secretion - hypokalaemia

Answer 244

Proton pump apically - pumps H+ out AE1 exchanges a bicarb out basally, brings in Cl- Cl- exits basally

Answer 245

AE1 - bicarb out apically, Cl- into cell Proton pump - pumps H+ out basally Cl- leaves basally

Answer 246

Low Na+ permeability High urea and H2O permeability in presence of ADH

Answer 247

Fall in GFR Impaired fluid and electrolyte homeostasis Accumulation of nitrogenous waste Needs dialysis

Answer 248

Hypervolaemia Hyperkalaemia Acidosis High urea and creatinine

Answer 249

Oliguria - due to hypotension - pre-renal cause Treated by IV saline, add HCO3-

Answer 250

PCT - 70% Loop - 20% DT and CD - 9% - by aldosterone

Answer 251

PT - 70% Loop - 5% DT and CD - 24% - by ADH

Answer 252

PT - 80% Loop - 20% DT and CD - only in aldosterone

Answer 253

By vagus nerve (parasymp) - depresses heart rate - this is called negative chronotropic action and is mediated by M2 acetylcholine receptors Symp - catecholamines increase HR by activating B1 adrenoreceptors - increases cAMP - PKA activation - activates L-type Ca channels and Ca channels on ER

Answer 254

He collected the fluid bathing heart and applied it on a different heart - it slowed - this meant that it was a chemical, not electrical, released from vagus nerve

Answer 255

1) Anesthetise the animal 2) Cut open chest and remove heart 3) Place heart in dish of warm Ringer's solution - press on heart slightly to remove any blood 4) Tie aorta to cannula and perfuse with warmed, aerated Ringer's solution - this perfuses the coronary arteries 5) Place in water jacket to keep heart warm 6) attach hook to apex of ventricles and connect to force transducer - allows us to convert physical movement to electrical signal

Answer 256

Supra-optic and paraventricular nuclei

Answer 257

Supra-optic and paraventricular nuclei detect a change of 3 mosmol/Kg of H2O (normal range is 280-300) Causes release of ADH and thirst - at normal osmolality there is still ADH in the plasma

Answer 258

Increase: water deficiency, stress, drugs (nicotine and ecstasy) Decrease: excessive fluid, drugs (alcohol)

Answer 259

ADH binds to a V2 receptor which causes insertion of AQP2 channels by activating PKA to stimulate vesicles - dilutes plasma - increases H2O reabsorption - fall in body osmolality - fast (~ 15 minutes)

Answer 260

Lots of dilute urine - we can use a desmopressin nasal spray to stop ADH release - we can defect the V2/AQP2 channels

Answer 261

Released from adrenal cortex - zona glomerulosa (mineralcorti) Regulates (increases) Na, K and body fluid volume Released in response to high K, low Na or low volume Acts on late distal/cortical and medullary collecting duct

Answer 262

1) binds to cytosolic mineralcorticoid receptor 2) transport to nucleus 3) increases expression of transport proteins 4) There will be Na reabsorption and K/H+ secretion Can take a few hours Na comes in via Na/H exchanger - goes to blood by Na/K pump - K leaves apically

Answer 263

1) binds to cytosolic mineralocorticoid receptor 2) transports to nucleus 3) increases transcription of protein transport channels 4) H+ is secreted

Answer 264

There is Na loss but high aldosterone - loss response There are mutations in mineralocorticoid receptor mutations

Answer 265

Body fluid volume, plasma Na and K+

Answer 266

Renin released from the juxtaglomerular apparatus Renin causes angiotensinogen to be converted to angiotensin 1 ACE1 (from lungs) causes angiotensin I to convert to angiotensin II

Answer 267

Causes zona glomerulosa to release aldosterone Vasoconstricts arterioles - increase BP ACE inhibitor - BP treatment

Answer 268

Internal - within the cell External - ventilation, gas exchange

Answer 269

External convection Pulmonary diffusion Internal convection Tissue diffusion

Answer 270

Trachea --> bronchi --> bronchioles (terminal and respiratory) --> alveoli (from terminal bronchiole) Conducting zone - air travel Respiratory zone - air diffusion

Answer 271

Nose, nasopharynx, oropharynx, pharynx, larynx, trachea, bronchial tree - filters, warms and humidifies air

Answer 272

Cartilage Smooth muscle Elastic tissue Mucous glands

Answer 273

Ciliated epithelia Goblet cells Sensory nerve endings

Answer 274

Lack of cartilage Has respiratory epithelium Has more smooth muscle than bronchi proportionally

Answer 275

Created by flattened cytoplasm of type I pneumocyte and capillary wall

Answer 276

Involves primary muscles: diaphragm and external intercostals - follows Boyle's law: pressure volume relationship

Answer 277

Uses primary muscles (diaphragm and external intercostals) and accessory (sternocleidomastoid, scalenes, back and neck) muscles

Answer 278

Passive - due to elastic recoil

Answer 279

Uses accessory muscles, internal intercostals, abdominal muscles and neck and back muscles

Answer 280

Pleural cavity - prevents lungs from sticking to wall or collapsing - allows free expansion Parietal is the outside Visceral is the inside

Answer 281

Collapsed lung

Answer 282

= distensibility c = change in volume/change in pressure low compliance = more work to inspire e.g. pulmonary fibrosis high compliance = more work expiring (less elastic recoil) e.g. emphysema

Answer 283

Anatomical - elastic nature and extracellular matrix Surface tension = due to differences in forces, there's a balance between pressure and surface tension

Answer 284

Pressure = 2(tension)/radius

Answer 285

Produced by type II pneumocytes - prevents alveoli collapsing and reduces surface tension

Answer 286

Anatomical - volume of conducting airways Physiological - volume of lungs not participating in gas exchange - conducting zone + non-functional respiratory zone

Answer 287

IRV - inspiratory reserve volume (maximum inspiration - tidal volume) FRC - functional residual capacity During exercise - changes Can't measure RV

Answer 288

Impact of resistance to flow R = (8/pi) x (viscocityXlength/radius ^4) R = 1/r^4

Answer 289

1.5 cm H2O.s.litres

Answer 290

Anything affecting airway diameter - increase mucus secretion - oedema - airway collapse

Answer 291

Parasymp - ACh from vagus acts on MAChR - constricts Symp - noradrenaline causes dilation Adrenaline in blood - dilation Histamine - constriction

Answer 292

Breathing with a balloon with helium - gets diluted (measure conc before and after)

Answer 293

yes! directly It is indirectly proportional to resistance

Answer 294

Pharynx/larynx - 40% Airways>diameter 2mm - 40% Airways

Answer 295

Dry (atmospheric) - mostly nitrogen (78%), then oxygen (21%) Wet (trachea) - similar but has H2O Henry's law: [gas] = solubility coefficient x pp

Answer 296

The total pressure of a mixture of gases is the sum of their individual partial pressures

Answer 297

Using Henry's law: [Gas]dis = s (solubility coefficient) x Partial pressure of gas

Answer 298

O2 is has a low solubility in saline - 0.003 ml/100ml blood This is too little so haemoglobin is needed

Answer 299

Tetrameric - 2 alpha and 2 beta Has a haem group and a globin chain Can be tensed (low O2 affinity) or relaxed (high O2 affinity)

Answer 300

Porphyrin ring with an iron atom For O2 to bind, iron must be in state Fe2+ Methaemoglobin reductase converts Fe3+ to Fe2+ Haemoglobin can be relaxed or tensed

Answer 301

X axis = pp of O2 Y axis = haemoglobin saturation Increases then plateaus At high temp = carries less, low temp = carry more At high pH = carries more, low pH = carries less - BOHR EFFECT At high 2,3 diphosphoglycerate conc = carries less, at low conc = carries more

Answer 302

- increased temp - increased CO2 production - decreased pH

Answer 303

Beta chains are replaced by y chains - left shift in curve - higher O2 affinity

Answer 304

CO2 + H2O <-> H2CO3 <-> HCO3- + H+ The blood can carry CO2 in many ways e.g. carbonic acid, bicarb, dissolved CO2 - grouped as total CO2

Answer 305

CO2 is in plasma - can remain or enter RBC - 10% remains Remain - can dissolve, bind to plasma protein, some form bicarb (slow with no carbonic anhydrase) Entering the RBC - can cross by AQP1 or Rh protein or diffuse through bilayer Some dissolves in RBC fluid, some bind to haemoglobin (Hb-NH-COO-) doesn't bind to iron, rest is converted to bicarb by carbonic anhydrase - bicarb can leave by bicarb/Cl exchanger When at lungs - this is reversed

Answer 306

Breaks down food into nutrients so we can use them for energy and growth& repair Eliminates waste and undigested food Helps regulate blood sugar, immune system, promote good mental health

Answer 307

A muscular tube - intestines are suspended in the cavity by mesenteries Hollow organs are separated by sphincters Accessory organs secrete into the lumen Functions include: Motility propels food, digestion, absorption

Answer 308

Mucosal layer: epithelia (villi), lamina propria (capillaries, enteric neurones, immune cells), thin muscularis mucosae Submucosal layer: connective tissue, glands, larger blood vessels Circular and longitudinal smooth muscle Serosa (squamous epithelia)

Answer 309

For mastication Has exocrine glands: lipase and amylase, saliva lubricates bolus, antimicrobial, buffers and dissolves food Sensory information is relayed to brainstem

Answer 310

Has stratified squamous epithelia Swallowing causes upper oesophageal sphincter to close - initiates peristaltic wave Continued distention = second peristaltic wave Vagovagal reflex controls lower oesophageal sphincter - PNS vagus does this

Answer 311

By three divisions of ANS: - extrinsic = PS + S - intrinsic = ENS (primary) ENS has two main plexuses - ganglia in submucosal and myenteric plexuses, submucosal is between mucosa and circular muscle, myenteric is between circular and longitudinal Lots of neurones - >100 million

Answer 312

Ganglia in plexuses coordinate information to SM, endocrine and secretory cells Postganglionic neurones are either cholinergic (ACh) or peptidergic (peptides e.g. substance P)

Answer 313

Postganglionic nerve fibres release noradrenaline - mixed efferent and afferent - relayed between GI tract and CNS

Answer 314

1) receptive relaxation in thin-walled orad (fundus and some body) stomach 2) 3 layers of caudad region (body and atrium) contract to mix food with gastric juices from mucosal glans (ANS control) - makes chyme - HCl, Pepsinogen --> pepsin, intrinsic factor, mucus 3) gastric emptying through pyloric sphincter into duodenum - fat and H+ slow this

Answer 315

Subthreshold slow waves produce weak contraction (tonic) Action potentials on top (phasic contractions) Low pressure organs separated by sphincters (6 + sphincter of oddi) Regulate antegrade (forward) and retrograde (backward) movement

Answer 316

Unitary smooth muscle - cells electrically coupled by gap junctions

Answer 317

Tonic - constant level of contraction Phasic - periodic contraction then relaxation Contraction is preceded by electrical activity - cells of cajal

Answer 318

Digestion and absorption of nutrients - chyme is mixed with digestive enzymes and pancreatic secretions There are many hydrolytic enzymes in brush border Duodenum --> jejunum --> ileum SA increases - plicae - villi - microvilli

Answer 319

Secretes pancreatic juice (1L daily) into duodenum - rich in bicarb (by centroacinar and ductal cells) to neutralise H+ - enzymes secreted by acinar cells PNS secretes, SNS inhibits In cephalic phase - gastic and intestinal

Answer 320

Pancreas, liver and gallbladder

Answer 321

Hepatocytes secrete bile - gall bladder stores and ejects - CCK is released from SI when chyme enters which relaxes sphincter of oddi

Answer 322

Water Amphipathic bile salts (aids fat digestion) Bilirubin Cholesterol Phospholipid Electrolytes - Na, K, HCO - 95% bile salts recirculate to liver by enterohepatic circulation

Answer 323

Peristaltic contractions propel chyme Segmentation contractions split and expose chyme to secretions - enterochromaffin cells release serotonin - peristaltic reflex Material not absorbed passes through ileocaecal sphincter into caecum of LI

Answer 324

GI peptides: - hormones e.g. GIP - paracrines e.g. somatostatin - neurocrines - from neurone after action potential

Answer 325

1) absorbs water and electrolytes (aldosterone increases Na absorption) 2) makes and absorbs vitamins K + B 3) forms and propels faeces

Answer 326

Surface columnar epithelium - interspersed with crypts Has taenia coli - 3 longitudinal muscles and haustra Caecum and proximal colon mix contents

Answer 327

Obstructive - reduced flow through airways Restrictive - reduced lung expansion Both reduce ventilation

Answer 328

Highest flow at low volume then gradual decreases Negative flow = flow out

Answer 329

Narrowing airways Could be due to: - excess secretions - bronchoconstriction (asthma) - inflammation Increased resistance FEV1<80% FVC FVC is usually normal - FEV1 affected There is a sharp fall in flow-volume - graph isn't a straight line (normal) - looks like a banana

Answer 330

Chronic bronchitis - persistant cough and mucus Asthma - inflammatory COPD Emphysema - loss of elastin

Answer 331

Hyper-active airways Trigger could be: - atopic (extrinsic) = allergies - non-atopic (intrinsic) = cold air, stress, exercise, drugs, irritants, resp infections Causes bronchoconstriction Short acting treatment = salbutamol (B2 adrenoreceptor agonist) Long acting treatment = inhaled glucocorticoid steroids or long acting B2 agonists

Answer 332

Reduced chest expansion - chest wall abnormalities, muscle contraction deficiencies Loss of compliance - ageing, increased collagen, environment Vital capacity is reduced - FEV1 is the same Flow-volume graph tends to be normal

Answer 333

Slow build up of fibrous tissue leading to loss of compliance

Answer 334

Dorsal respiratory group - controls inspiration by sending signals to inspiratory muscles - spontaneously active Ventral respiratory group - controls inspiration and expiration - inactive during quiet respiration - helps when forceful

Answer 335

Pneumotaxic centre - increases breathing rate by shortening inspiration - inhibitory effect on inspiratory centre Apneustic centre - increases depth and reduces breathing rate by prolonging inspiration - stims inspiratory centre

Answer 336

Yes! Hering-Breuer reflex - stretch receptors in lungs send signals to medulla and limit inspiration and prevent over-inflation Phrenic nerve --> diaphragm --> lung stretch receptor --> vagus nerve --> inspiratory centre inhibited

Answer 337

Yes! Central: monitor CSF CO2 and pH - if rise in CO2 - increase ventilation Peripheral: in carotid body and aortic arch - respond to increased CO2, decreased pH, decreased O2 - increases ventilation

Answer 338

Provides breathing rhythm - pattern generator

Answer 339

Controlled by hormonal, paracrine and neurocrine control. >9L of fluid daily - most absorbed in SI - rest lost in LI or in faeces Salt and water balance regulates ECF volume and BP

Answer 340

Distal: gastrin, somatostatin, pepsinogens Proximal: HCl, pepsinogens, intrinsic factor, mucins, bicarb

Answer 341

Secretion Motor Humoral (gastrin, somatostatin)

Answer 342

Mucosal layer Secrete >2L daily Body: oxyntic glands - epithelial cells (bicarb) - mucous neck cells (mucus) - Parietal cells (HCl, intrinsic factor) - enterochromaffin-like cells (histamine) Antrum: pyloric glands (same as pyloric but no parietal cells) - G cells (gastrin hormone) - Chief cells (pepsinogen) - enterochromaffin cells (serotonin, VIP, substance P) - D cells (Somatostatin)

Answer 343

Protective: - Bicarb - neutralises acid and combines with mucus to form a protective barrier - Mucus - protects epithelia Hydrolytic: - HCl - activated pepsinogen and denatures proteins - Pepsinogen - precursor of pepsin - digests protein Endocrine: - Gastrin - increases HCl secretion and pepsinnogen release- Intrinsic factor - B12 absorption Histamine - increases parietal cell HCl secretion Serotonin/VIP - motility and secretion, VIP decreases HCl Substance P - SM contract Somatostatin - inhibit gastrin release

Answer 344

While resting: cytoplasmic pool of tubulovesicular membrane - contains acid secreting H,K-ATPase Stimulated: induces cytoskeletal changes - tubulovesicular and canalicular membranes fuse - increases SA by 50/100x, microvilli are present, insertion of H,K-ATPase pump, K+ + Cl- channels

Answer 345

H2CO3 in the cell - H+ is secreted apically through H+/K+ ATPase Cl- follows out HCO3- absorbed into blood via Cl--bicarb exchanger There are Na/K+ exchangers basally Theres K+ channels allowing K+ to exit the cell apically

Answer 346

Stimulation: ACh (Vagus), histamine (ECL) and gastrin (G cells) Inhibition: low pH, somatostatin, prostaglandins

Answer 347

SI and LI have crypts of leiberkuhn - secrete fluid and electrolytes Si absorb fluid and Na/K/Cl/bicarb by villi, Li by surface epithelia Crypt epithelial cells - secrete fluid + electrolytes - protective LI - has a net absorption of water/ Na/ Cl, secretes bicarb and K SI - have plicae (folds of kerckring), villi and microvilli - increase SA by 600x Duodenum and jejunum is the primary site for Na/Cl/K/bicarb absorption

Answer 348

In epithelial cell of crypts of leiberkuhn Na/K/Cl cotransporter brings ions into the cell from the blood Cl diffuses into the lumen through Cl channels - open when cAMP increases due to GPCR - open by ACh/VIP ect. Na follows paracellularly (passive) Water follows

Answer 349

All Na absorption - Na/K ATPase Low intracellular Na (by sodium potassium exchanger) drives entry via Na channels/ Na-H exchangers/ Na-glucose/aa cotransport - secondary active transport The Na/H exchangers are stimulated by bicarb Net absorption of NaHCO3

Answer 350

Same as jejunum but also involves Cl Has a bicarb/Cl exchanger which brings Cl into the cell There is a Cl transporter - Cl absorbed Net NaCl into cell

Answer 351

Acinar cells secrete CCK Bicarb secreted into pancreatic juice by Cl/bicarb exchanger H is transported into blood by NaH exchanger Net secretion of bicarb and H absorption Ductal cells - recs for CCK, ACh and secretin to upregulate production

Answer 352

Aldosterone causes Na to enter colon cell apically Na leaves into blood by Na/K ATPase This brings in potassium - leaves apically

Answer 353

Carbohydrases: alpha/beta amylase, maltase, sucrase, trehelase, lactase ---- into villus blood Protease: pepsin, trypsin, chymotrypsin, elastase, carboxypeptidases ---- into villus blood Lipases and bile salts ---- into lacteals in villus

Answer 354

Epithelial cells SGLT1 - brings Na and Glucose/galactose in GLUT5 - brings fructose in GLUT2 - takes all sugars to blood Na/K pump basally

Answer 355

Na brings in amino acids H brings in di/tripeptides - peptidases break them down in the cell A channel takes AAs into blood Theres a NA/H exchanger apically Na/K pump basally

Answer 356

Pancreatic lipase and other lipids hydrolyse by bile salts in duodenum and jejunum Products: cholestrol, lysophospholipids, monoglycerides, micelles (have amphipathic bile salts) In mucous gel layer epithelia - FAs become protonated and cross the enterocyte by diffusion, carrier mediated transport, incorporated into membrane Products are resterfied in SER - packaged into chylomicrons - absorbed into lacteals

Answer 357

In kidneys Beta cells (65%) - insulin, pro insulin, C peptide, amylin Alpha cells (20%) - glucagon Delta cells (10%) - somatostatin There are also: F cells - pancreatic polypeptide e cells - ghrelin protein enterochrommafin cells - not in islets Richly perfused with blood

Answer 358

Small arteries enter islet - distribute by fenestrated capillaries Vascular arrangement

Answer 359

Gap junctions between beta and alpha cells Delta cells send dendrite-like processes to beta cells

Answer 360

Adrenergic, cholinergic and peptidergic neurones

Answer 361

High blood glucose stimulates Symp stimulation: Beta-adrenergic increases secretion, alpha decreases Parasymp stimulation: vagus ACh increases release GIP (SI K cells), Amylin (beta cells) and somatostatin Drugs e.g. sulphonylureas act on KATP increasing insulin secretion

Answer 362

GLUT2 lets glucose in - makes ATP from glycolysis ATP closes k+ channels - depolarisation Ca channels open causing exocytosis CCK acetylcholine - Gq coupled Somatostatin decreases, Glucagon and beta adrenergic agonists increases

Answer 363

Heterotetramer - alpha/beta subunits + IC tyrosine kinase Receptor activation activates or inhibits - PKC, phosphatases, phospholipases, G proteins Causes cell growth, division, gene expression High insulin levels --> receptor downregulation

Answer 364

Binds to receptor --> signal transduction cascade --> causes exocytosis of a vesicle with GLUT4 ---> allows glucose to enter Target all cells - especially muscle and liver to make glycogen - increases fat cell glucose intake when glycogen levels replenish

Answer 365

Promotes glycogenesis Inhibits glycogenolysis Inhibits gluconeogenesis

Answer 366

1) Promotes glucose uptake (GLUT4) 2) Promotes glycogen synthesis 3) Promotes glycolysis and carbohydrate oxidation 4) Promotes proteinsynthesis and inhibits protein breakdown

Answer 367

Increases GLUT4 expression, converts glucose to FAs (stores as triglycerides), increases lipoprotein lipase - makes triglycerides from FAs, inhibits oxidation of fat Overall decreases levels of FAs and keto acids

Answer 368

Promotes K+ uptake through Na/K ATPase This effects hypothalamic satiety centre

Answer 369

This is where there is islet destruction - autoimmune There is hyperglycaemia and increased blood fatty acids and keto acids Hyperkalaemia Hypotension Polyuria Symptoms: hunger, increased thirst, weight loss, fatigue, fruity breath, blurred vision Treatment: insulin replacement therapy

Answer 370

Insulin resistance Symptoms: increased thirst, hunger, urination, weight loss, headaches, tired, blurred vision Treatments: sulphonyurea drugs e.g. tolbutamide (stimulate insulin secretion), biguanide drugs e.g. metformin (upregulate receptors on targets), weight control

Answer 371

- Produces haploid gametes - Facilitate fertilisation with spermatozoan - Site for implantation of the embryo - Provide physical and nutritional needs to nurture baby (mammary glands)

Answer 372

Female gonads - mature ova Medulla - blood vessels and lymph Cortex - outer epithelia layer containing oocytes (in a follicle - folliculogenesis) Follicular cells secrete steroid hormones: - granulosa - 17b oestrogen - theca - progesterone Primary follicle - graafian follicle - corpus luteum

Answer 373

Transport egg to uterus - 10cm Has Isthmus -> ampulla -> infundibulum with fimbriae. Smooth muscle (circular & longitudinal) in walls - peristalsis Has highly folded mucosa - ciliated and secretory cells

Answer 374

Perimetrium (outer) Myometrium Endometrium

Answer 375

Uterus inner layer Simple columnar with leukocytes and macrophages Lamina propria - lots of connective tissue Compound tubular glands Has spiral arteries

Answer 376

Connects uterus to vagina Has external and internal os Cervical glands secrete mucus - prevents microbes

Answer 377

Birth canal 8-10cm Thin wall of: - adventitia - muscularis - mucosa Has stratified squamous epithelium (with glycogen) which ferments to lactic acid to prevent bacteria Also has dendritic cells

Answer 378

Ovarian (follicular and luteal) and endometrial (menstrual) (menses, proliferative and secretory)

Answer 379

The hypothalamic-pituitary-gonadal axis - hypothalamic neurones release gonadotropin-releasing hormones (GnRH) This travels to the anterior pituitary by the hypophyseal portal system GPCRs on pituitary (gonadotrophs) release gonadotropins: - FSH - LH

Answer 380

Stim ovarian follicular cells to secrete steroid hormones: progesterone (theca cells) and 17b-oestrodoil (granulosa - these also release inhibin (decreases FSH) and activin (increases FSH)) This produces mature gametes LH - triggers ovulation FSH - grows and matures follicles

Answer 381

HPGA is controlled by +ve and -ve feedback Follicular phase: 17b-oestrodiol - -ve feedback Luteal phase: progesterone - -ve feedback Ovulation (midcycle): follicular cell proliferation, oestrodoil rapidly decreases - +ve feedback - more FSH/LH - triggers ovulation of oocyte

Answer 382

Follicular - FSH/LH - increases follicles so there is a surge of oestrogen as they are making more (proliferative phase) The oestrogen reaches a point where it causes positive feedback - LH and FSH - ovulation happens Luteal - corpus luteum secretes progesterone - this stimulates endometrial glands - they will secrete (secretory phase) At day 22 - corpus luteum will degenerate - endometrium is lost - as oestrogen and progesterone is falling

Answer 383

17B-oestrodiol and progesterone cause the changes

Answer 384

Follicular: mucus copious, watery and elastic, forms channels to propel sperm Secretory: mucus is thick

Answer 385

In endometrial cycle 17B-oestrodiol increases loads Causes growth of: - endometrum - glands - stroma - spiral arteries elongate

Answer 386

After ovulation - dominated by progesterone Proliferation slows - thickness decreases Glands have glycogen and mucus Spiral arteries elongate and coil Ends in menses

Answer 387

- oestrogen and progesterone - decreases LH/FSH so no ovulation or folliculogenesis - progesterone only - monophasic (fixed dose) - multiphasic (varying dose)

Answer 388

Only progesterone Thick cervical mucus - no sperm penetration Less uterus and fallopian tube motility Less endometrial glycogen

Answer 389

High oestrogen and progesterone dose - interferes with implantation - inhibit ovulation - thickens mucus so sperm can't reach

Answer 390

Some feedback on hypothalamus - less GnRH - low FSH and LH - no ovulation or folliculogenesis

Answer 391

Gametes are transported to the ampulla of the oviduct The oocyte is surrounded by granulosa cells Sperm(150-600 million): capacitation, SM contraction and cervical mucus helps the sperm The sperm penetrates via an acrosomal reaction This activates the oocyte - increases calcium - causes 2nd meiotic division and prevents another sperm in (polyploidy) The haploid pronuclei fuse = diploid zygote Happens early in fallopian tube

Answer 392

Move along oviduct for three days - nourished by oviduct secretions - isthmus contractions slow it down to allow endometrium to prepare Will divide until 8 - then becomes morula then blastocyst - then implanted (6 days)

Answer 393

Before implantation - fluid filled cavity. Lined by trophoectoderm layer - this makes the yolk sac, fetal placenta and amnion

Answer 394

At 6-10 days after ovulation Blastocyst promotes stromal cells from endometrium to transform into decidual cells (predecidualisation) Endometrial reception to blastocyst - low oestrodiol:progesterone (secretory phase) There is several parts of the invasion

Answer 395

In blastocyst: - inner cytotrophoblast: single mitotic layer which differentiates into syncytiotrophoblast - outer syncytiotrophoblast: produces hormones e.g. HCG

Answer 396

1) Hatching: zona pellucida (outer layer) degenerates due to lytic factors - releasing inner cells 2) Apposition: the trophoblastic and endometrial epithelium meet 3) Adhesion: intracellular and extracellular integrins bind to receptors on the deciduous endometrium 4) Invasion: syncytiotrophoblast cells penetrates endometrium

Answer 397

Zona pellucida

Answer 398

Allows materials to pass from maternal system to foetus Have 120 spiral arteries from the mother - empty into intervillous places - washes over foetal projections and decreases the force from the mothers blood Syncytiotrophoblast lacunae - merge and fill with maternal blood Syncytiotrophoblast and cytotrophoblast form villi and microvilli

Answer 399

- foetal capillary epithelium - mesenchyme - cytotrophoblasts - syncytiotrophoblasts

Answer 400

From maternal: - glucose (fac diff) - amino acids (2nd active transport) - vitamins (active transport) - antibodies/hormones (endocytosis) From foetal: - waste urea and creatinine

Answer 401

Trophoblast: HCG (rescues the corpus luteum) - up to week 9 Corpus luteum: progesterone and oestrogen to support endometrium

Answer 402

Placenta: steroid hormones. This includes human placental lactogens (hCS) which: - coordinate fuel economy - develop mammary glands Progesterone from cholesterol Oestrogen from foetal-placental

Answer 403

Stage 0 (quiescence): before birth, uterus is relaxed and insensitive to uterotonic hormones, progesterone suppresses myometrial contractions, braxton-hicks

Answer 404

Stage 1 (activation): cortisol increases by H-P-adrenal axis - this increases oestrogen - contracts and stimulates prostaglandin release (promotes formation of gap junctions and softens and thins cervix) Contraction- associated proteins are expressed e.g. uterotonic recs of oxytocin Enzymes to hydrolyse collagen are expressed

Answer 405

Stimulation of birth: PG increase: myometrial contraction, cervical dilation Increased myometrial connectivity and responsiveness positive feedback loops: ferguson reflex and uterine contraction increasing PG + oxytocin Labour: dilation --> expulsion --> placental

Answer 406

Recovery from birth Haemostasis - vasoconstriction of spiral arteries Decrease in oestrogen - myometrium will regress The endometrial lining will reestablish after 3-5 months

Answer 407

From secretory unit of breast = alveoli (contractile cells and adipose tissue) During pregnancy: oest and prog stim breast growth, oest will stimulate anterior pituitary to release prolactin but prog and oest prevent it acting on breast Postpartum: oest increases cell proliferation, prolactin initiates milk, oxytocin increases contraction and release of milk, prolactin and cortisol maintain milk

Answer 408

For milk production Inhibiting dopamine releases prolactin from anterior pituitary Oxytocin is released from posterior pituitary Downregulates GnRH to inhibit ovarian cycle

Answer 409

Look on the lab on lt

Answer 410

+ve - left ankle -ve - right wrist earth - left wrist If the electrical vector moves towards +ve vector - positive defection

Answer 411

Mitral - left Tricuspid - right

Introduction To Pharmacology Flashcards

(436 cards)